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bioRxiv · 10.1101/2020.12.22.424017

15-PGDH as a Negative Regulator of Age-Related Organ Fitness

Abstract

Emerging evidence implicates the eicosanoid molecule prostaglandin E2 (PGE2) in conferring a regenerative phenotype to multiple organ systems following tissue injury. As aging is in part characterized by loss of tissue stem cells regenerative capacity, we tested the hypothesis that the prostaglandin-degrading enzyme 15-hydroxyprostaglandin dehydrogenase (15-PGDH) contributes to the diminished organ fitness of aged mice. Here we demonstrate that genetic loss of 15-PGDH (Hpgd) confers a protective effect on aging of murine hematopoietic and gastrointestinal (GI) tissues. Aged mice lacking 15-PGDH display increased hematopoietic output as assessed by peripheral blood cell counts, bone marrow and splenic stem cell compartments, and accelerated post-transplantation recovery compared to their WT counterparts. Loss of Hpgd expression also resulted in enhanced GI fitness and reduced local inflammation in response to colitis. Together these results suggest that 15-PGDH negatively regulates aged tissue regeneration, and that 15-PGDH inhibition may be a viable therapeutic strategy to ameliorate age-associated loss of organ fitness. ARTICLE SUMMARY15-PGDH as a Driver of Age-Related Tissue Dysfunction

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Ho, W. J., Smith, J. N. P., Park, Y. S., Hadiono, M., Christo, K. F., Jogasuria, A., Zhang, Y., Broncano, A. V., Kasturi, L., Dawson, D. M., Gerson, S. L., Markowitz, S. D., Desai, A. B.. 2020-12-22. 15-PGDH as a Negative Regulator of Age-Related Organ Fitness. https://doi.org/10.1101/2020.12.22.424017

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